A farmer grows wheat, barley, and oats on her 500 -acre farm. Each acre of wheat requires 3 days of labor (to plant, tend, and harvest) and costs $21 (for seed, fertilizer, and pesticides), each acre of barley requires 2 days of labor and costs $27, and each acre of oats requires 3 days of labor and costs $24. The farmer and her hired field hands can provide no more than 1200 days of labor this year, and she can afford to spend no more than $15,120. If the expected profit is $50 for each acre of wheat, $40 for each acre of barley, and $45 for each acre of oats, how many acres of each crop should she grow to obtain the greatest possible profit